Machine for the fabrication of spiral tube coils



Jan. 22, 1963 HUET 3,074,465

MACHINE FOR THE FABRICATION OF SPIRAL TUBE COILS Filed Jan. 26, 1959 3 Sheets-Sheet 1 FIGZ) INVENTOR. I ANDRE HUET ATTORNEY Jan. 22, 1963 A. HUET 3,074,465

MACHINE FOR THE FABRICATION OF SPIRAL TUBE COILS Filed Jan. 26, 1959 3 Sheets-Sheet 2 FIG. 4

INVENTOR. ANDRE HUET ATTORNEY A. HUET Jan. 22, 1963 MACHINE FOR THE FABRICATION OF SPIRAL TUBE COILS 3 Sheets-Sheet 3 Filed Jan. 26, 1959 FIG. 7

FIG. 6

INVENTOR. ANDRE HUET ATTORNEY United rates 3,074,465 MACHINE FOR TEE FABRICATION F SPRAL TUBE COILS Andre Huet, Paris, France, assignor to Combustion Engineering Inc, New York, N.Y., a corporation of Delaware Filed Jan. 26, 1959, Ser. No. 789,009 7 Claims priority, application France Feb. 3, 1958 Claims. (Cl. 15364) The present invention relates to an improved machine for winding a metallic tube into a spiral form of relatively wide pitch.

It often happens in the construction of heat exchangers that it becomes necessary to manufacture parts consisting of spirally wound tubes forming a succession of whorls more or less spread out. One method practiced heretofore of producing the spiral tube is by drawing it on a rotating cylinder formed with suitable grooves and around which the tube is wound up.

This invention is concerned with a machine to manufacture spiral tube coils, particularly applicable to tubes of non-circular section but which are, for instance, flattened out to an either lentil or egg shape of more or less complex form. These tubes are generally obtained by deformation of a tube, originally of circular shape, by more or less flattening it out between suitable dies. Such flattened tubes cannot be spirally wound up with ordinary machines because the traction exerted on the tube would bring about a deformation harmful to the flattened section of the tube which is less resistant than the circular shape.

A characteristic of a machine embodying the invention lies in the fact that during the whole process of manufacture of whorls, the tube is subjected to a thrust which does not produce any deformation in the shape of the tube, instead of being subjected as usual to traction. In accordance with the invention, a thrusting force exerted through a series of driving rollers is applied to the surface of the tube to be bent and forces the tube to pass between the driving rollers and a bending roller which is located opposite a pair of support rollers and between them. The bending roller is applied against the tube by a jack bearing on a joint in the form of a knee and causing the bending of that tube portion involved, following a certain arch corresponding to the spiral winding intended to obtain while the whole unit swings carrying the bending roller and the driving rollers which results in that it is not necessary to modify the direction of the tube before bending. Afterwards the constant thrust exerted on the advancing straight part of the tube continues to ensure the bending of the tube by means of the bending roller while other spacing rollers, adjustable in position, contact the section of the tube already bent to ensure the spacing of the whorls which are forming in order to execute the coiling of the tube in spiral form at the desired pitch.

The following description of an illustrative embodiment of the invention when read in connection with the attached drawings will afford an understanding of the method in which the invention can be executed.

FIGURE 1 is a schematic side elevational view of a machine embodying the invention showing the tube as it reaches the bending station of the said machine.

FIGURE 2 is an enlarged view of part of FIG. 1 illustrating the relationships after the bending of the first whorl in the tube.

FIGURE 3 is a detailed cross-sectional view on a larger scale, through the axis of the driving rollers for the tube.

FIGURE 4 shows on even larger scale than FIGURE 3,074,465 Patented Jan. 22, 1963 2 the mounting of the spacing rollers on the bending unit of the machine.

FIGURE 5 is a plan view, partly cut away corresponding to FIGURE 4.

FIGURE 6 shows schematically a plan View of a roller arrangement for maintaining the inside spacing of the whorls of the tube spiral.

FIGURE 7 is an elevational view of the same parts illustrated in FIG. 6 but supplemented by a frame bearing rollers for maintaining the outside spacing of the whorls of the spiral.

A machine embodying this invention as shown in FIGS. 1 and 2 has a series of feeding rollers 10 located above lower supporting rollers 12 so as to form pairs of rollers between which a tube A to be treated passes. -It will be noted, in FIG. 3 particularly, that the section of tube A is deformed, i.e. that it is of a generally flattened or lenticular shape in accordance with two convex faces the one B which is the upper face of the tube on FIG. 3 being of a fairly semi-elliptical shape, while the other C is more distinctly convex. Tube A is fed forwardly between rollers 10 and 12 as shown in FIGS. 1 and 3. The driving members are the rollers 10 which are actuated through driving pinions 14, FIG. 5. The support rollers 12 are applied against the tube and rollers 10 by means of jacks 16 fed to a common pipe line 17 and to the rods of which jack levers 18 are hinged, the levers 18 being pivotally connected at their ends to the axes of two adjacent rollers 12. In this manner the pressure exerted by rollers 12 on tube -A is rather supple so as to adapt itself to the variations in the forward motion and the friction of tube A resulting from the bending stress of the tube, as will be explained later. In order to increase the thrust exerted on tube A by the series of rollers 11 sanders 20 are provided between the rollers 10 for increasing the grip between the upper face B of the tube and the driving rollers 14 At the front end of the machine the straight tube A passes on to two rollers 22 and 24 whose axes are mounted on a side-plate in two double pieces 26 and 28, and the Whole so is mounted to oscillate around axis 27 of roller 22. A bending roller 30 is mounted opposite roll ers 22 and 24 in relation to tube A on a slide 32 permitting a translation of movement of the axis of roller 30 on side plate 26. On the other hand, slide 32 is connected by a system of hinged rods forming a toggle 34, 36 to a rod 38 mounted in adjustable manner between two screw nuts 46 and forming a fixed point on side plate 28. The toggle 34, 36 is likewise hinged to the piston 42 of a jack 44 pivoted at 45 and supported by side plate 28. On the axis of bending roller 3% there furthermore is hinged a rod Sil the other end of which has a slot 51 through which passes a fixed pin 52 carried by a bracket 53 forming an integral part of the bed plate 54 of the machine. This limits the extreme oscillating movement of the oscillating unit.

The two side plates 26 and 28 with the devices they carry are in the position shown in FIG. 1 at the beginning of the tube bending operation so that the straight tube A fits between the bending roller 30 and the support rollers 22 and 2 At this moment hydraulic presure is applied to jack 44, the rod 42 of which pushes on toggle 34, 36 straightening it in order to slide the bending roller 30 towards the lower part of FIG. 1. Thus roller 30 penetrates between support rollers 22, 24 in such manner that the end portion of the tube A is bent concavely while the same stroke by reaction swings the side plates unit 26, 28 and the apparatus which they carry in the direction of arrow F (FIG. 1) around the rotating axis 27 of roller 22 until taking up a balanced position shown in FIG. 2. This position which is the result of the location of bending roller 30 in relation to driving rollers 22 and 24 at the same time determines the radius of the bending arch given to the tube A at the time of its passage between these three rollers; this also is the position which will be adopted by the parts described for the continuation of the process and .for obtaining a spiral tube wound up as though on a cylinder of determined diameter. Therefore, the whole oscillating unit 26, 28 etc. is immobilized by means, for instance, of a hook 55 hinged on bed plate 54 of the machine in the said position and engaging a detent 56 on side plate 28. A turnbuckle arrangement 57 allows control of the effective length of hook 55 according to the angular position which the oscillating unit itself has taken up during the bending operation.

As soon as tube A is bent, as shown in FIG. 2, over a certain length called base ring the tube advances to pass between spacing rollers 60, 61, and 62 mounted on stub shafts carried on slides 63 in guides 64- projecting from the side faces of side plates 26, 28 as appears in FIGS. 4 and 5. These rollers are not shown in FIGS. 1 and 2 for clearness sake. Rollers 6i and 61 should preferably have a groove profiled to correspond to a tube section of lenticular shape. They press against the section of tube A and each of these rollers is mounted in such manner that it can take up any desired position. In this manner roller 61 (FIG. 5) is mounted on slide base 63 which can slide in a slotted guide 64 and be immobilized in the desired position there by means of a screw 65'. Further, guide block 64 is mounted in a direction at right angles so that it can slide, for instance, in a fantail groove 66 foreseen on the supporting side plate 28 and a screw system permits to immobilize guide block 64- in any desired position. It can be seen that with this possibility of sliding in two perpendicular directions into the space above roller 22, rollers 60, 61 and 62 can take up any desired position on the section of tube A, as shown in FIG. 5. These rollers then operate so as to continuously move consecu tive portions of tube A, wound up in a circle out of the vertical admission plane for the tube and to adjust the spacing of the whorls progressively as they are formed, since these rollers are at different distances progressing outwardly away from plate 28. In this manner the suitable pitch for the spiral, the beginning of which can be seen in FIG. 5, is obtained. The middle parts of rollers 22 and 30 are in the admission plane of the tube determined by the series of rollers and 12. To the contrary,

the other support roller 24 is already somewhat staggered out of this plane and away from plate 28 (towards the lower part of FIG. 5) ie that it is already in position to permit an initial spacing of the bent portion of the tube in order to lead to the formation of the final whorl.

As whorls E form successively, FIG. 6, it is provided without this being indispensable for the functioning of the machine, to rectify or maintain the inside and outside spacing of the whorls wound up spirally in relation to the axis of the spiral. This can be accomplished by means of a system of rollers or cylindrical rolls pressing against the whorls from the outside and the inside.

The system is shown in FIGS. 6 and 7. Three cylindrical rolls 7t 71, 72 are mounted in clevises on threaded rods permitting to set them in position on a central hub 73. The axes of the threaded rods are at 120 one from the other, so that the three rollers 70-72 are spread out over the inner surface of the whorls as shown in FIG. 7. A stud 74, integral with the machine bed plate 54 prevents the rotation, by transmission around its axis, of hub 73 which represents the axis of the manufactured tube spiral.

Progressively with the output of the machine, the spiral passes over rollers 70-72 each of them remaining perceptibly in the position shown in FIG. 7 and ensuring in such manner the adjustment or maintenance of the inside spacing of the whorls.

At the outside a similar arrangement consists of three cylinders or rollers 75, 76, 77 arranged in adjustable manner inside of a frame 78 as shown in FlG. 7. Frame 78 is mounted on a carriage 80 which can slide on a rail 81.

Furthermore, frame 7 8 is hinged at 82 to its carriage and a system of clamping devices 85 pivoted at 86 on the carriage 80 permits giving frame 73 any desired angular position in relation to carriage 8t), and to immobilize it in this position by tightening lever 87. This arrangement is also adaptable to all dimensions of the pitch and to the dimeter of the spiral which it is desired to obtain; Put into place on the first whorls effected by the machine, it is then immobilized and ensures the identity of the following whorls produced by the machine.

In order to manufacture tube spirals of any pitch and of any desired diameter the machine is adjusted in the following manner. The adjustment of the diameter is effected by adjusting on side plate 28 the fixed fulcrum point 35 of toggle 34, 36 by means of screws 38 which permit to vary the position of this fixed point on which rests the toggle, which will be pushed by jack 44. It can be seen in fact that by getting closer to or farther away from the fixed point 35 on which rod 34 hinges (FIG. 2) the rate of progress and the position taken by bending roller 3%} in relation to rollers 22, 2.4 is determined. Furthermore, the position of the axis of driving roller 24 can be adjusted on side plate 26 by shifting its axis 90 in a slot 92 of the supporting side plate 26 (FIGS. 1 and 2) where the said axis is immobilized at the desired distance. These adjustments determine the diameter of the cylinder of the spiral which will be formed from tube A. The pitch of the winding up of this spiral as on a cylinder will result from the position given to spacing rollers 60, 61, 62 (FIGS. 4 and 5) which determine the space established between them by the successive whorls.

Although the machine has been described as being applicable especially to tubes having a deformed shape, it should be understood that it can also be utilized for bending tubes of circular section into tubes of deformed shape. It sufiices to give to the grooves of the driving rollers 10, 12 shapes which are progressively variable in order to transform the circular shape into the desired shape. This transformation can also be effected during bending operation itself by means of bending rollers 22 and 24, the grooves of which can be shaped in such manner as to produce not only the bending, but also the desired deformation of the tube section.

What I claim is:

1. A machine for bending a tubular member to a spiral coil form comprising; a frame pivotally mounted at a bending station; a pair of spaced tube supporting rollers carried by said frame in a position to receive and support the tube; a reciprocable tube bending member mounted on said frame at one side of and intermediate said support rollers; means for moving and guiding said bending member into engagement with the face of said tube located away from said support rollers to force the portion of the tube supported on said support rollers between the latter to exert a bending force on said tube member; and means for pivoting said frame in a direction to cause the bending force exerted on said tube to force the latter to assume a circular curvature corresponding to the diameter of the spiral being formed from the tube.

2. A machine for bending a tubular member to a spiral coil form comprising; a frame pivotally mounted at a bending station; a pair of spaced tube supporting rollers carried by said frame in a position to receive and support the tube; a reciprocable tube bending roller mounted on said frame at one side of andintermediate said support rollers; means for moving and guiding said bending roller into engagement with the face of said tube located away from said support rollers to force the portion of the tube supported on said support rollers between the latter to exert a bending force on said tube and means for pivoting said frame in a rearward direction about the axis of the rearward one of said support rollers to cause the bending force exerted on said tube to force the latter to assume a circular curvature corresponding to the diameter of the spiral being formed from the tube.

3. A machine as recited in claim 1 wherein there are arranged at the outlet end of the machine, around and at the inside of the spiral whorls formed in the tube, systems of rollers pressing from inside and outside against the whorls formed in order to adjust their dimensions.

References Cited in the file of this patent UNITED STATES PATENTS tHaldeman Apr. 16, 1918 Mertz May 13, 1941 De Witt Dec. 9, 1952 Hesterman Apr. 21, 1953 

1. A MACHINE FOR BENDING A TUBULAR MEMBER TO A SPIRAL COIL FORM COMPRISING; A FRAME PIVOTALLY MOUNTED AT A BENDING STATION; A PAIR OF SPACED TUBE SUPPORTING ROLLERS CARRIED BY SAID FRAME IN A POSITION TO RECEIVE AND SUPPORT THE TUBE; A RECIPROCABLE TUBE BENDING MEMBER MOUNTED ON SAID FRAME AT ONE SIDE OF AN INTERMEDIATE SAID SUPPORT ROLLERS; MEANS FOR MOVING AND GUIDING SAID BENDING MEMBER INTO ENGAGEMENT WITH THE FACE OF SAID TUBE LOCATED AWAY FROM SAID SUPPORT ROLLERS TO FORCE THE PORTION OF THE TUBE SUPPORTED ON SAID SUPPORT ROLLERS BETWEEN THE LATTER TO EXERT A BENDING FORCE ON SAID TUBE MEMBER; AND MEANS FOR PIVOTING SAID FRAME IN A DIRECTION TO CAUSE THE BENDING FORCE EXERTED ON SAID TUBE TO FORCE THE LATTER TO ASSUME A CIRCULAR CURVATURE CORRESPONDING TO THE DIAMETER OF THE SPIRAL BEING FORMED FROM THE TUBE. 